01350nas a2200145   4500008004100000245009100041210006900132260001400201300001200215490000700227520087200234100002501106700002301131856005001154       1997                        eng d00aOrigins and nature of vessels in monocotyledons. 2. Juncaginaceae and Scheuchzeriaceae0 aOrigins and nature of vessels in monocotyledons 2 Juncaginaceae   c23-1-1997  a397-4010 v173 aSEM studies of roots and rhizomes of Triglochin (one species) and Maundia (monotypic) of Juncaginaceae and the sole species of Scheuchzeriaceae, Scheuchzeria palustris, reveals that vessels are present not only in roots, as previously reported, but also in rhizomes. The perforations contain pit membranes with pores of various sizes. Striate pit membranes, like those previously seen in Acorus, occur on pit remnants in perforations and on pit membranes of lateral walls in all genera studied. Grooves interconnecting pit apertures are illustrated for root tracheary elements of Triglochin; this is believed to be a first report of this feature for monocotyledons. The tracheary elements of Juncaginaceae and Scheuchzeriaceae are similar in their thick walls and narrow slitlike pits, lending support to the close relationship between the two families often claimed.1 aSchneider, Edward, L1 aCarlquist, Sherwin  uhttps://juncaginaceae.myspecies.info/node/316